JPS59128998A - Electric blower - Google Patents

Abstract

PURPOSE:To improve efficiency by installing a plurality of vanes having an inclination descending toward the direction of revolution of an impeller, onto the inside surface of the intake port of a casing and providing preturning and downward force for the standstill stream and introducing air stream smoothly into the impeller. CONSTITUTION:A plurality of vanes 17 are installed onto an intake hole 12 at the center part of a casing 11. Said vane 17 is inclined in descent in the direction of revolution of an impeller 14, and the inclination angle is 40 deg. with respect to the axial direction. Since the standstill air stream passes through the vane 17 before entering into the impeller 14 by the use of an electric blower, said standstill air stream is provided with pre-turning in the same direction to the revolution of the impeller 14. Therefore, a large amount of air stream is smoothly introduced into the impeller 14, and the efficiency is improved. Thus, the load of the imepller 14 can be reduced and the loss due to the slip of the air stream can be prevented, and generation of surging can be prevented by the rectification effect of the air stream.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an electric blower used in a vacuum cleaner or the like.

Conventional Structure and Problems Electric blowers used in vacuum cleaners have heretofore been constructed in such a way that a centrifugal impeller is directly connected to a high-speed rotating commutator motor. By using this commutator motor, the motor can be made smaller, taller, and more connected than an induction motor. However, in the case of a commutator motor, since the temperature rises during operation is large, it is necessary to cool the motor, and this is generally cooled by airflow discharged from an impeller.

Therefore, the structure is such that the airflow discharged from the impeller passes through a passage leading into the inside of the motor.

In models using centrifugal impellers, the impeller generates kinetic energy, or dynamic pressure, and pressure energy, or static pressure, and converts this dynamic pressure into static pressure, increasing efficiency. There is. As a means of converting this dynamic pressure into static pressure, a polycoat portion is provided around the impeller.

The polycoat part and the exhaust passage are integrated around the impeller for the two purposes shown above, namely, converting dynamic pressure into static pressure17 and guiding airflow into the motor. Those equipped with an air guide are common.

Fig. 1 shows the general configuration of an electric blower. 1 is a casing, with an intake port 2 opened in the center, and a motor frame 3 on the opposite side from the casing to prevent air leakage. is attached to. 4 is a plurality of blades 4a
A centrifugal impeller 6 has a volute portion 6a for converting the dynamic pressure generated by the impeller 4 into static pressure,
This air guide is integrally formed with an exhaust passage 5b that guides the discharge airflow from the impeller 4 into the motor. 6 is a motor that drives the impeller 4.

When the impeller 4 is rotated by the motor 6, air is sucked in through the intake port 2 of the casing 1, and the air is sucked through the impeller 4, the volute portion 5a of the air guide 5, the exhaust passage 5b, and the motor 6.
It passes through the inside of the body and is discharged to the outside.

Now, considering the intake airflow of an electric blower, the intake airflow to the impeller 4 enters the impeller 4 through the intake port 2 from a static state in the atmosphere. This is due to the suction caused by the action of centrifugal force generated by the rotation of the impeller 4, and the inhaled airflow is given a dynamic pressure component and is discharged to the air guide 5 provided around the outer periphery of the impeller 4 as a discharged airflow. The discharged airflow is converted into static pressure by the volute section 5a and enters the motor 6 through the exhaust passage b. The efficiency of the impeller 4 is determined by how many dynamic pressure components are converted into static pressure components. That is, it depends on how much the impeller 4 discharges the dynamic pressure component.

However, the above-mentioned configuration has a drawback in that a static airflow in the atmosphere is directly guided to the impeller 4 for intake, so that a sufficiently smooth intake state of airflow cannot be created.

OBJECTS OF THE INVENTION The present invention provides an electric blower that improves the above-mentioned conventional air intake condition and efficiently guides static air flow to the impeller.

Structure of the Invention The electric blower of the present invention has a structure in which a plurality of blades are provided on the inner surface of the intake port of the casing, and the blades are inclined downward in the direction of rotation of the impeller. easier to empower,
It is also designed to smoothly guide airflow to the impeller.

DESCRIPTION OF EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS. 2 to 4. In the figure, reference numeral 11 denotes a casing with an intake port 12 opened in its center, and the opposite side of the casing from the intake port 12 is attached to a motor frame 13 attached to the motor so as to prevent air leakage. 1.4 is multiple blades 4
A centrifugal impeller 15 is an air guide in which a volute portion 151L for converting the dynamic pressure of the air flow generated by the impeller 14 into static pressure and an exhaust passage 15b are integrally formed. The impeller 14 is enclosed by the casing 11.

Reference numeral 16 denotes a motor 1 that drives the impeller 14, and a blade 17 is provided at the air intake port 12 in the center of the casing 11.
The blades 17 are inclined downward as they rotate in the direction of rotation of the impeller 14, and the angle of inclination is 40 degrees with respect to the axial direction. The blades 17 are installed so as not to overlap each other in the vertical direction, and there are four blades arranged at 90 degrees. The thickness of the blade 17 is required to not become a resistance to the intake flow rate and to have sufficient strength, and is set to t = 2 mm in the embodiment. Further, both ends of the blade 17 have a streamlined shape with low air resistance.

In the above configuration V, by using an electric blower, the stationary airflow passes through the blades 17 before entering the impeller 14, and the stationary airflow is given a pre-swivel in the same rotational direction as the impeller 14, and is further directed downward. The power of is also given at the same time. As a result, a large amount of airflow smoothly enters the impeller 14, thereby increasing efficiency. That is, it is possible to reduce the load on the impeller 14 and prevent loss due to airflow slipping.
Furthermore, the effect of suppressing surging due to the airflow rectification effect is outstanding.

Effects of the Invention The electric blower of the present invention has a configuration in which blades are provided at the intake port of the casing, so that a large amount of airflow can be smoothly guided into the impeller, reducing the load on the impeller and the slip loss of the airflow. It can improve the efficiency of the output, and it solves the conventional problem.

[Brief explanation of drawings]

Fig. 1 is a partially cutaway side view of a conventional electric blower, Fig. 2 is a partially cutaway side view of an electric blower showing an embodiment of the present invention, and Fig. 3 is a partially cutaway side view of the electric blower. FIG. 4 is a plan view of the intake port portion, and is a view taken from the direction of arrow A in FIG. 3. 11... Casing, 12... Intake port, 14... Impeller, 16... Air guide, 17... Vane. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
figure

Claims (1)

[Claims] It consists of a motor, a motor frame attached to the motor, an air guide and an impeller attached to the upper surface of the motor frame, and a casing containing them. Electric blower equipped with multiple blades having a downward slope in the direction 0